Polyesters and lactones are useful commercial materials which may be prepared by various methods. The starting materials used in some of the known methods are:
1. Diols+dicarboxylic acids; PA0 2. Diols+anhydrides of dicarboxylic acids; PA0 3. Diols+dichlorides of dicarboxylic acids; PA0 4. Diols+esters of dicarboxylic acids; PA0 5. Lactones; PA0 6. Hydroxy carboxylic acids; PA0 Fe.sub.3 (CO).sub.12 PA0 Ir.sub.4 (CO).sub.12 PA0 Os.sub.3 (CO).sub.12 PA0 Rh.sub.6 (CO).sub.16 PA0 Ru.sub.3 (CO).sub.12 PA0 H.sub.2 Ru.sub.4 (CO).sub.12 PA0 [(PhCO.sub.2)(CO).sub.3 Ru].sub.2 PA0 Fe.sub.3 (CO).sub.12 /Ru.sub.3 (CO).sub.12 PA0 Os.sub.3 (CO).sub.12 /Rh.sub.6 (CO).sub.16 PA0 Ru.sub.3 (CO).sub.12 /Ir.sub.4 (CO).sub.12 etc. PA0 RuCl.sub.2 (PPh.sub.3).sub.3 PA0 RuH.sub.2 (PPh.sub.3).sub.4 PA0 RuH.sub.2 (CO)(PPh.sub.3).sub.3 PA0 RuHCl(CO)[P(C.sub.6 H.sub.11).sub.3 ].sub.3 PA0 RuCl.sub.3 PA0 RhCl(PPh.sub.3).sub.3 PA0 RhH(PPh.sub.3).sub.4 PA0 Rh(1,5-COD)(PR.sub.3)Cl PA0 IrCl(CO)(PPh.sub.3).sub.2 PA0 Ir(Bipyridine)(1,5-COD)Cl PA0 Ru.sub.3 (CO).sub.12, Os.sub.3 (CO).sub.12, Fe.sub.3 (CO).sub.12, H.sub.2 Ru.sub.4 (CO).sub.12.
Usually the synthesis of dicarboxylic acids, anhydrides, dichlorides and esters require the oxidation of diols according to the following scheme: ##STR1## Thus, diols serve as chemical precursors for the preparation of dicarboxylic acid, their anhydrides, dichlorides and esters which then in conjunction with the diols yield the desired polyesters by known methods.